Hypothetical Tornadoes Wiki:2020 Stuart, Florida tornado (unfinished)
The July 15, 2020 tornado was a powerful multiple-vortex EF4 (rating disputed) that struck the city of Stuart during the afternoon of a hot summer day. The tornado was not part of an outbreak, although a Severe Thunderstorm Watch was issued by the National Weather Service prior to the event due to the presence of atmospheric conditions that were uncommon for the season. The tornado initially formed at 4:53 p.m EDT as a very thin waterspout on the St. Lucie River, traveling downstream to the southeast as it gained strength. The tornado remained on the ground for approximately 20 minutes (after making landfall from the river), measuring 3/4 of a mile wide at it's peak. Before striking North River Shores Boat Camp, it followed the river almost exactly. Meteorological synopsis On July 9, National Weather Service meteorologists introduced a 15% risk area for the entire state of Florida in their Day 4-8 outlook. Model forecasts before the severe probability mention had hinted at a summer cold front making a successful push through the deep south. These cold fronts rarely reach the southern Florida peninsula during the summer season. However, as forecasts began to solidify, it became apparent that a strong cold front would pass clear through the entire state, from northwest to southeast. During the summer, thunderstorms are a daily occurrence throughout most of Florida due to diurnal heating and the formation of the east and west coast sea-breezes. The severe outlook mentioned the probability of the west coast sea-breeze being dominant, and the cold front propelling and strengthening the eastward-moving storms during mid to late-afternoon - the peak of diurnally-driven convection. Hail and straight-line winds were thought to be the main threat, and approaching the date, a moderate risk area was ultimately introduced. Although a small tornado threat was included, the event was expected to develop derecho-like characteristics as the cold front outpaced the inland-moving west coast sea-breeze. The east coast sea-breeze was expected to remain suppressed for most of the day, but forecasts hinted at a threat of increased tornadic activity if the sea-breeze did indeed develop within a certain window of time. On July 15, 11:30 a.m EDT, the Storm Prediction Center issued a severe thunderstorm watch for all counties from Volusia to Miami-Dade as the storms on the west coast began to strengthen and trigger multiple severe-warned cells in that area. Storm development and track The parent thunderstorm of the Stuart tornado had developed over an hour before the event. At 3:45 p.m, a robust thunderstorm with frequent lightning and hail - eventually becoming half-dollar sized - began to develop off the coast of Lake Okeechobee, to the east of the city of Okeechobee. It appeared to make a bee-line, at first, towards Port St. Lucie. However, the storm became nearly stationary as it intensified due to the collision of the sea-breezes, heavily flooding rural areas and destroying two homes with downburst winds. It moved very little for approximately 30 minutes, while during this time a wind gust of 80 mph and another at 87 mph were observed by storm spotters. Extensive tree damage occurred before the cell was shunted east-southeast as the cold front approached.